Along with rapid development of a display technology, a touch panel has been widely used in human life. Generally, in terms of composition structure, touch panels can be divided into: an add-on touch panel, an on-cell touch panel, and an in-cell touch panel. The add-on touch panel has a touch panel and a display panel (Liquid Crystal Display) separately produced and bonded together to form a display screen with a touch function. The add-on touch panel has many shortcomings such as high production cost, low light transmittance, and thick module and so on. The in-cell touch panel is to embed touch electrodes of the touch panel in a display screen, which not only reduces overall thickness of the module, but also greatly reduces production cost of the touch panel, and thus is favored by panel manufacturers.
Generally, the in-cell touch panel is to detect a finger touch position by using the principle of mutual-capacitance or self-capacitance. For example, a plurality of self-capacitive electrodes arranged in a same layer and insulated from each other can be arranged in a touch panel by using the principle of self-capacitance. When a human body does not touch the screen, capacitances of respective self-capacitive electrodes are a constant value; when the human body touches the screen, the capacitance of corresponding self-capacitive electrode is a sum of the constant value and the capacitance of human body. A touch chip can determine a touch position by detecting changes in capacitance values of respective self-capacitive electrodes during a touch period. As compared with mutual-capacitive touch panel where the capacitance of human body can only act on a projected capacitance, the capacitance of human body can act on all the self-capacitances in self-capacitive touch panel, and thus touch changes caused by touching the screen by the human body are greater than that of a touch panel fabricated by using the principle of mutual-capacitance. Therefore, the self-capacitive touch panel can effectively improve a signal-to-noise ratio of touch, so that accuracy of touch sensing is improved.